CVE-2026-126210
@hono/node-server: Backslash in the request path is parsed as a path separator, bypassing path-based access control at a reverse proxy
@hono/node-server allows running the Hono application on Node.js. Prior to 1.19.18 and from 2.0.0 until 2.1.6, the server passes a raw request-target containing a backslash in its path to the WHATWG URL parser, which treats the backslash as a path separator and resolves dot segments. A reverse proxy, load balancer, or web application firewall that preserves the backslash and applies path-based rules to the original request can therefore permit a request that the application normalizes to a blocked route. This lets an unauthenticated client reach route content that the upstream component was intended to deny, while Hono application access controls are unaffected because they operate on the normalized path. This issue is fixed in versions 1.19.18 and 2.1.6.
Fixes and workarounds
Fix
@hono/node-server (npm): OSV reports a fixed version 2.1.6. Check the advisory for supported release branches.
Source: OSV GHSA-jpvv-r467-5p4wFix
@hono/node-server (npm): OSV reports a fixed version 1.19.18. Check the advisory for supported release branches.
Source: OSV GHSA-jpvv-r467-5p4wAffected products and versions
| Product | Versions | Authority |
|---|---|---|
| node-server honojs |
>= 2.0.0, < 2.1.6 (affected) < 1.19.18 (affected) |
CNA: GitHub_M |
@hono/node-server@hono/node-server
npm |
≥ 2.0.0; < 2.1.6 (affected, semver); OSV events: introduced 2.0.0; fixed 2.1.6Source events (semver)Other versions: unaffected |
OSV GHSA-jpvv-r467-5p4w |
@hono/node-server@hono/node-server
npm |
≥ 0; < 1.19.18 (affected, semver); OSV events: introduced 0; fixed 1.19.18Source events (semver)Other versions: unaffected |
OSV GHSA-jpvv-r467-5p4w |
Version ranges are source assertions. Check the vendor advisory and your installed configuration before determining exposure.
CVSS assessments
| Version / score | Vector | Authority |
|---|---|---|
| 3.1 / 5.3 medium |
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N | CNA: GitHub_M |
| 3.1 / 5.3 medium |
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N | NVD: [email protected] |
Exploit evidence
No exploit evidence in collected sources. This is not proof of no exploitation.
References
- https://github.com/honojs/node-server/security/advisories/GHSA-jpvv-r467-5p4wCNA: GitHub_M · x_refsource_CONFIRM
- https://github.com/honojs/node-server/commit/3868998a805ae79216535ad3986c1e7228dee313CNA: GitHub_M · x_refsource_MISC
- https://github.com/honojs/node-server/commit/fb97395ec36af66567c76976e741110b02804d1cCNA: GitHub_M · x_refsource_MISC
- https://github.com/honojs/node-server/releases/tag/v1.19.18CNA: GitHub_M · x_refsource_MISC
- https://github.com/honojs/node-server/releases/tag/v2.1.6CNA: GitHub_M · x_refsource_MISC
- https://github.com/honojs/node-server/commit/3868998a805ae79216535ad3986c1e7228dee313[email protected]
- https://github.com/honojs/node-server/commit/fb97395ec36af66567c76976e741110b02804d1c[email protected]
- https://github.com/honojs/node-server/releases/tag/v1.19.18[email protected]
- https://github.com/honojs/node-server/releases/tag/v2.1.6[email protected]
- https://github.com/honojs/node-server/security/advisories/GHSA-jpvv-r467-5p4w[email protected]
- https://github.com/advisories/GHSA-jpvv-r467-5p4wOSV / GitHub Security Advisories · advisory
- https://osv.dev/vulnerability/GHSA-jpvv-r467-5p4wOSV / GitHub Security Advisories · osv
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